YM3711 vaccination effectively reduced not only Aβ1-42 but also other Aβ species.

YM3711 at a dose of 100 µg was injected weekly to 15-month old model mice for 6 weeks and the brain and plasma were taken at 8 weeks. Immunostaining for Aβ revealed that compared with untreated control mice (A), Aβ deposits in the frontal cortex were clearly decreased in vaccinated mice (B). Bar = 100 µm. Quantitative analysis by sandwich ELISA (C–E) demonstrated the significant reduction of Aβ1-42 in treated mice (C) (p = 0.0254). AβpE3-42 (D) and Aβ oligomer (E) quantitation also revealed significant reduction in the YM3711-treated group (p = 0.0433 and p = 0.0074, respectively). Aβ species that are recognized by anti-amyloid fibrils, OC, were semiquantitated by measuring densities of 56 kD band (F). Aβ fibrils were significantly reduced in treated Tg mice than in control Tg mice (p = 0.01). Closed and open columns indicate the amount of Aβ species in the cerebral cortex of vaccinated mice (n = 4) and of age-matched control mice (n = 5), respectively.